The correct answer is :
A second voice
Explanation:
As no genuine independent other voice exists, this is a form of heterophony. In its earliest stages, organum needed two musical voices: a Gregorian chant melody, and the same music transferred by a consonant interim, regularly a complete fifth or fourth.
Answer:
Organum added what to Gregorian chants?
Guitar music
A choir
A second voice
Lyre accompaniment
Explanation:
A second voice
